It is sometimes desirable or necessary to obtain specimens of tissue from humans and other animals, particularly in the diagnosis and treatment of patients with cancerous tumors, premalignant conditions, and other diseases or disorders. For example, when it is discovered that suspicious conditions exist, either by means of x-ray or ultrasound imaging in various tissues of the body, a physician usually performs a biopsy to determine if the cells at the suspected site are cancerous or benign.
A biopsy can be done either by an open or percutaneous technique. Open biopsy is an invasive procedure using a scalpel, by either a portion (incisional biopsy) being removed or the entire mass (excisional biopsy) is removed. Percutaneous biopsy is usually done with a needle-like instrument through a relatively small incision, and can be performed by fine needle aspiration (FNA) or through the taking of a core biopsy sample. In FNA biopsy, individual cells or clusters of cells are obtained for cytologic examination and can be prepared such as in a Papanicolaou smear. In a core biopsy, a core or fragment of the tissue is obtained for histologic examination.
Uncontaminated and intact tissue from the organ, lesion, or tumor is preferred by medical personnel in order to arrive at a definitive diagnosis regarding the patient's condition. In most cases only part of the tissue in question needs to be sampled. The portions of tissue extracted must be indicative of the organ, lesion, or tumor as a whole. Often, multiple tissue samples from various locations of the mass being sampled may be taken.
The percutaneous biopsy procedure can be performed utilizing various techniques and devices. One such biopsy device can include an inner stylet positioned inside an outer cannula, where the stylet is able to slide into and out of the cannula. The stylet can be a solid, pointed needle having a tissue sampling recess, and the cannula can be a hollow, open-ended needle having a sharp tip. The stylet and cannula can be manipulated cooperatively to capture a tissue sample in the sample recess. Such existing devices can be manually operated, semi-automated, and automated.
U.S. Pat. No. 6,485,436 shows a multiple sample biopsy needle with a hydraulic mechanism that circulates fluid from the tip of the needle back to a receiving basket or baskets. A revolver-type array of receiving chambers is disclosed.
U.S. Pat. No. 5,827,305 shows a tissue sampling needle that pushes a sample proximally using a saline wash. Samples remain spaced apart within the needle such that the sequence of their collection is preserved. Samples can also be removed from a port while the needle remains in place. No mechanical transport mechanisms or drives are disclosed.
U.S. Pat. No. 5,526,822 shows a transport system that uses a cannula and knock-out pin combined with a vacuum source to shuttle a tissue sample to a multiple-chamber cassette where it is knocked out. The cannula is then repositioned for another sample. The vacuum source is external. A revolving sample cassette is also shown. A vent opening in each sample cylinder of the cassette is provided to eject the fluid used to transport the tissue sample. A removable disposable needle-bearing cassette interfaces with rotary and linear drives by means of long gears and shuttles that cradle the gears. Cutters operate in rotary and linear fashion (a counter-rotating cutters embodiment is included) and the cannula can be rotated to orient the sample opening.
U.S. Pat. No. 6,017,316 shows a transport system similar to U.S. Pat. No. 5,827,822 in which a cutter transports with vacuum assist. Multiple sampling with single insertion is described but not automated multiple sample-handling. The details of a drive system are not disclosed
U.S. Pat. No. 6,193,673 shows a needle with a durable part and a disposable part. An external cutting cannula rotates and advances axially to cut a sample. The tissue cutter is driven axially by a rack and pinion drive which are part of a durable component. A cradle connects the rack to the cutting cannula.
U.S. Pat. No. 5,944,673 describes a tissue extractor that rotates within a piercing needle to align with any one of multiple receiving ports while obstructing the remaining ports. The tissue sample is cut by advancing the cutter and removing by withdrawing the extractor. A vacuum holds the tissue sample in place during the removal of the tissue extractor from the cutter. The cutter rotates as it advances.
It is known to obtain a single sample with a single insertion. However, there are circumstances where there may be a need to obtain more than one sample. While the known biopsy needle can be re-inserted multiple times, such technique can cause pain and scarring of the body site.
It is known to leave a marker at the biopsied site. To do so, however, a physician or healthcare provider would typically need to withdraw the biopsy needle and insert a different device to leave a marker at the biopsied site. The additional step with the marker device concurrent with the tissue sampling may not allow the marker to be deposited at the actual biopsied site, which can lead to inaccurate post-biopsy diagnosis.
There is a need in the art for improved systems for performing multiple sample biopsies, particularly systems that are amenable to self-contained designs and improved techniques for sample extraction and handling. There is also a need for efficient and precise marker delivery with minimal trauma.